665683751 has 2 divisors, whose sum is σ = 665683752. Its totient is φ = 665683750.

The previous prime is 665683727. The next prime is 665683769. The reversal of 665683751 is 157386566.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-665683751 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 665683696 and 665683705.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665683721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332841875 + 332841876.

It is an arithmetic number, because the mean of its divisors is an integer number (332841876).

Almost surely, 2^665683751 is an apocalyptic number.

665683751 is a deficient number, since it is larger than the sum of its proper divisors (1).

665683751 is an equidigital number, since it uses as much as digits as its factorization.

665683751 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 907200, while the sum is 47.

The square root of 665683751 is about 25800.8478736649. The cubic root of 665683751 is about 873.1509256043.

The spelling of 665683751 in words is "six hundred sixty-five million, six hundred eighty-three thousand, seven hundred fifty-one".